Study has been carried out for automatic control mode concerning drum-level of a 35 t/h CFB boiler for municipal solid waste (MSW) incineration. Directing against the present situation of comparatively large load fluctuation in the furnace of MSW incinerator

and compavatively poor adjusting accuracy of actuator for feed-water control valve

on the basis of traditional three impulse cascade control mode

the PID control parameters of the main loop and the auxiliary loop have been sectionally adjusted by adopting fuzzy control strategy

emphasizing the isolating function of PID parameters during the time of controlled parameter being in different ranges

at the same time an asynchronous control pattern is adopted for the main and auxiliary control loops

enhancing greatly the regulating accuracy of water-level in the boiler durm

decreasing the number of oscillation in water-level regulation.